Re: [ANNOUNCE][CFT] kexec for v2.5.48 && kexec-tools-1.7 -- Success Story!

Andy Pfiffer
2002-11-19T17:14:18Z

On Tue, 2002-11-19 at 02:25, Eric W. Biederman wrote:
> > Complete kernel boot-up log attached below. I'm going to try to find my
> > other 576MB of RAM with the right command-line magic... ;^)
>
> Or you can write a routine to gather that information dynamically and send
> me a patch for /sbin/kexec. Though it may take another proc file to do
> that one properly.
>
> Eric

Just to make sure I understand the problem. Until we can make all
boot-time BIOS calls work, we need a way to:

1) capture the initial memory map used by the kernel, and
2) a way to supply that information to the to-be-run image.

On my system, the e820 map looks like this (from full reboot):
BIOS-provided physical RAM map:
BIOS-e820: 0000000000000000 - 000000000009dc00 (usable)
BIOS-e820: 000000000009dc00 - 00000000000a0000 (reserved)
BIOS-e820: 00000000000e0000 - 0000000000100000 (reserved)
BIOS-e820: 0000000000100000 - 0000000027fed140 (usable)
BIOS-e820: 0000000027fed140 - 0000000027ff0000 (ACPI data)
BIOS-e820: 0000000027ff0000 - 0000000028000000 (reserved)
BIOS-e820: 00000000fec00000 - 0000000100000000 (reserved)
639MB LOWMEM available.

And /proc/iomem looks like this:
00000000-0009dbff : System RAM
0009dc00-0009ffff : reserved
000a0000-000bffff : Video RAM area
000c0000-000c7fff : Video ROM
000ca000-000cb7ff : Extension ROM
000cb800-000cffff : Extension ROM
000f0000-000fffff : System ROM
00100000-27fed13f : System RAM
00100000-00309f9a : Kernel code
00309f9b-003d873f : Kernel data
27fed140-27feffff : ACPI Tables
27ff0000-27ffffff : reserved
effff000-efffffff : Adaptec AIC-7892P U160/m
effff000-efffffff : aic7xxx
f0000000-f7ffffff : S3 Inc. Savage 4
fea00000-feafffff : Intel Corp. 82557/8/9 [Ethernet
fea00000-feafffff : e100
feb7e000-feb7efff : ServerWorks OSB4/CSB5 USB Contro
feb7f000-feb7ffff : Intel Corp. 82557/8/9 [Ethernet
feb7f000-feb7ffff : e100
feb80000-febfffff : S3 Inc. Savage 4
fec00000-ffffffff : reserved

Comparing the two:
Range e820 /proc/iomem
0000000-0009dbff usable System RAM
0100000-27fed140 usable System RAM

>From a sample of 1 system, it looks like we should be able to use any
ranges marked as "System RAM" that are listed /proc/iomem. Did I miss
something?

I'll see if I can conjure up something...

Andy